1. Technical Field of the Invention
The present invention relates to an intermediate product manufacturing apparatus and an intermediate product manufacturing method for manufacturing intermediate products such as semiconductor wafers.
2. Description of the Related Art
Semiconductor processing apparatuses for manufacturing semiconductor wafers (hereinafter, referred to as wafers) include a variety of wafer processing apparatuses such as lithography apparatuses, film forming apparatuses, etching apparatuses, cleaning apparatuses, inspection apparatuses, etc.
Wafer cassettes are used for moving the wafers among the wafer processing apparatuses. The wafer cassettes detachably receive a plurality of wafers. A plurality of wafers corresponding to lots required by a process carrying system are housed in the wafer cassettes (for example, see Japanese Unexamined Patent Application Publication No. 62-48038 (see page 2 and FIG. 1)).
On the other hand, from the requirement for limited production of a wide variety of wafers, a so-called single wafer carrying method of carrying wafers on a conveyer one by one in place of carrying the wafers in wafer cassettes has been disclosed. This single wafer carrying method is intended to cope with the limited production of a variety of wafers (for example, see Japanese Unexamined Patent Application Publication No. 2002-334917 (see page 1 and FIG. 1)).
When the single wafer carrying method is employed, the following problems are caused.
One single wafer carrying conveyer is provided correspondingly to a plurality of processing apparatuses. That is, the single wafer carrying conveyer supplies the wafers to the respective processing apparatuses by using a single wafer carrying method. The single wafer carrying conveyer and the plurality of processing apparatuses constitute one process system.
Another process system is provided adjacent thereto. This process system is also provided with a single wafer carrying conveyer and a plurality of processing apparatuses. In a manufacturing system in which multiple process systems are arranged, a processing apparatus having the same processing function may exist in each adjacent process system.
Such a processing apparatus is, for example, a film thickness inspecting apparatus. The film thickness inspecting apparatus has a high film thickness inspection processing capacity, so that one film thickness inspecting apparatus can perform the film thickness inspection processing of all of the wafers in two adjacent process systems.
Therefore, processing apparatuses such as CVD (Chemical Vapor Deposition) apparatuses having a relatively low processing capacity, and apparatuses such as film thickness inspecting apparatuses having a relatively high processing capacity are repeatedly arranged in the single wafer carrying conveyers of the process systems. Since the number of apparatuses is large, the capital investment is increased.
When it is intended to transfer a wafer from one single wafer carrying conveyer to another single wafer carrying conveyer, the wafer is temporarily stored in a wafer cassette. The cassette is transferred to the next process system by using an inter-process carrying conveyer. The wafer is taken out of the cassette, and then the wafer should be transferred to the single wafer carrying conveyer of the next process system. For this reason, much time is required for taking in and out the wafers. Therefore, wafer manufacturing time cannot be reduced by sharing high volume processing apparatuses among more than one process system.
Therefore, the present invention is contrived to solve the above problems, and it is thus an object of the present invention to provide an intermediate product manufacturing apparatus and an intermediate product manufacturing method, capable of reducing the manufacturing time for intermediate products such as semiconductor wafers, and accomplishing miniaturization of the intermediate product manufacturing apparatus by allowing adjacent process systems to share an apparatus having a relatively high processing capacity.